Hello, I have an AEG microwave, 6 years old. When I turn the button to chose the cookingtime and the WATT , the display shows what I choosed so thats OK. When i then press the start button the microwave gives one click but it doesn't start cooking. A red light besides the WATT button however lights up.

The sounder is an integral part of the control board.

Power Failure, Demo Appears On Display And It Won'T Heat Up

https://www.aeg.co.uk > Support > Ovens
Dec 10, 2021 - 1. Switch on device and select "basic settings" using · 2. Select "demo mode" · 3. Select "off" and enter code "2468" using the up and down arrows.
Missing: MBE2658SE ‎' Must include: MBE2658SE

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  Turning AEG Command Wheel Oven Demo Mode On and Off ...

  https://www.aeg.co.uk > Support > Ovens
  Jun 2, 2020 - Demo mode allows live appliances to be demonstrated in store safely without heating up and becoming a safety risk. If you need to turn demo ...

how old is ur microwave ?
most probably its dead, if warranty available take it to the authorized repair center.

Normally when no power coming on from the microwave the fuse has blown in the microwave due to a short hi voltage diode con bad located by the capacitor or micro switches located by the door clips. If you have no electrical experience do not temp to fix it yourself due to high voltage stored in the capacitor.

The keypad has a short in the membrane, which means the keypad control board will probably need to be replaced.

Hello :

This happens because of a bad door switch . The plastic mounts inside the microwave which hold the door switches and onto which the door latches lock when you close the door .

best regards .

please don't forget to rate !

The owner's manual is here. On page 10 we find:

COOKING IN ONE STAGE
1. Press the POWER button; the Microwave and High
Cook indicators will light and “PL 10” will light in the
display.
2. Press the POWER button different times to set the
desired power; the display will show the percentage
you chose. If selecting power level 70%-10%, the
Low Cook indicator will light instead of the High
Cook indicator.
3. Press number keys to set the desired cooking time.
OPERATION(CONTINUED)
4. Press the START/+30SEC. button to start cooking;
the Microwave and one of the Cook indicators will
blink and the display will countdown the remaining
cooking time in minutes and seconds. It will beep
five times when cooking is completed.

We're happy to help you with free advice and we'd appreciate your thoughtful rating of our answer.

22 years old and you are complaining that it starts andomly, you got way more than your moneys worth for heavens sake loosen up and buy a new one. Help the economy out.

You are correct. The keypad is failing.

If you might want to replace it yourself, I have uploaded a handy guide with pictures showing you what's typically involved.

If you would like to have us do this for you, we do that for $39.95 plus part costs, assuming we can get the part for this Canadian model.

We're happy to help and we appreciate your thoughtful rating of our answer.

William E. Miller, AS-EET
[email protected]
http://www.microwavedisplay.com

Could you be more specific as to what it's doing and not doing and when? Thanks.